The Riddles of Manawydan

What is the water you cannot drink?
What is the mineral that kills and cures?
What is the ship you cannot sink?
What is the light that warns and lures?
Who sings the song that robs and feeds?
Who are the horses that run without feet?
Where is the cloak that was shaken between?
Why does the sea yearn for the land?
Why is this seafarer land bound?

Sea at Blackpool